OpenFields

Salads, slurry and irrigation: quantifying and minimising the risk

A study of the persistence of human pathogens from slurry on ready-to-eat salads and a set of recommendations for growers arising from it.

Year of Publication2009

Human pathogens from slurry can contaminate salad crops directly by infection of irrigation water or indirectly by splash from contaminated soil. Bacterial pathogens on leaves decline to absence in 14 to 21 days. Pathogens in soil can persist for six weeks and re-contaminate the crop if the soil is splashed by large irrigation or rainfall droplets. Growers are recommended to monitor the microbiology of irrigation water, use potable water within 3 weeks of harvest and minimise soil splash.